1. Technical Field
This invention relates to a control apparatus for an automatic transmission.
2. Background Art
In an automatic transmission for changing an output of a prime mover to be mounted on a vehicle in speed and transmitting it to a driven wheel, since hydraulic pressure supply is controlled by energizing and deenergizing an electromagnetic control valve, e.g., a linear solenoid valve, installed in a hydraulic pressure supply device to carry out the shifting (gear change) operation. Accordingly, the characteristic variability of the electromagnetic control valve needs to be eliminated.
To cope with it, Japanese Laid-Open Patent Application 2007-205501 proposes a learning control technique to learn the characteristic variability of the electromagnetic control valve and based thereon, correct a current supply command so that hydraulic pressure to be supplied to the automatic transmission converges to a desired value.